; 将定义的各个字符串转换为大写
assume cs:code,ds:data,ss:stack
stack segment
    dw 0,0,0,0
stack ends
data segment
    db 'abc.............'
    db 'def.............'
    db 'ghi.............'
    db 'kjl.............'
data ends
code segment
start:
    mov ax,data
    mov ds,ax
    mov ax,stack
    mov ss,ax
    mov sp,8
    mov bx,0
    mov cx,4
    l1:
        push cx
        mov si,0
        mov cx,3
        l2:
            mov al,[bx+si]
            and al,11011111b
            mov [bx+si],al
            inc si
            loop l2
        add bx,16
        pop cx
        loop l1   

    mov ax,4c00h
    int 21h
code ends
end start